Method of jointlessly welding rails



June 3, 1930. STEDEFELD 1,762,086

METHOD OF JOINTLESSIJY WELDING RAILS Original Filed Feb. 8, 1928 r 2 Sheets-Sheet 1 June 3, 1930.

C. STEDEFELD .'METHOD OF JOINTLESSLY WELDING RAILS Original Filed Feb. ,8, 1925 2 Sheets-Sheet 2 u f 5 a X6 O'O Patented June 3, 1930 CUB'I. STEDEFELD, OF HEIDELBERG, GE

METHOID OF JOINTLESSLY WELDING RAILS Original application .flled Tebruary 8, 1928, Serial No. 252,932, and in Germany December 27, 1926. Divided and this application filed. February 27, 1930. Serial No. 431,854.

Not only in tramway tracks in cities, but also in overland and long distance railway tracks the fish-plate joints with gaps to compensate for the vexpansion caused by changes 6 in temperature between the joining ends of the rails have been recently replaced by jointless welded joints. Generally the expansion gaps are-stillprovided at greater distances from one another, but it can be '1 expected, considering the present state of the are, that railway tracks having all joints welded, without any expansion gaps, may be constructed with reliability of service. In

railway tracks, where expansion gaps sepa This involves a number of new problems, the" solutions ofwhich are given. by the present invention.

' As a first example the welding of the last joint between the rails of a track which has been erected from two end points will be considered, or the repairing or renewal of a defective place in a completely Welded railway track.

,In well suited methods of welding railoints for instance in the alumino-therminal (thermit) butt welding and the electricbutt. welding and particularly in the melting-off welding method the rail ends must be moved longitudinally with relation to each other. This is possible with compara: tively simple apparatus when the welded rails have expansion gaps at not too reat distances from one'another. "The pro lem is diflerent when the expansion gaps lie far apart, or when no such gaps are provided. In the first case a very great length of the track must be dismounted, and furthermore it is not easy to move this length .in the manner required for welding, for instance with the melting-01f method. In the second case the possibility of movement disappears entirely with the omission of theexpansion gaps.

Referring to the drawings:

Figs. 1 and 2 are a side elevation and a plan view, respectively, of a track struc- 66 ture; I

. Fig. 3 is a detail showinga gap between rails; v Fig. 4 is another detail showing an overlap of rails;

Figs. 5 and 6 are diagrammatic views illustrative of the invention;

- Fig. 7 is a view partially in cross-section showing one form of the bending apparatus including the control means therefor;

Fig. 8 is a sectional viewof one of the control 'valves'shown in Fig. 7 and Fig. 9 is a diagrammatic showing of a modified arrangement wherein springs are employed to effect the bending.

The fundamental idea of the method ac-v cordingto this invention is shown; in Figs.

1 and 2. The previously described longitudinal movements are replaced by bending one rail 1 crosswise with respect to the other 75 rail at the joint, while the end of the other rail 2 is held firmly in the clamping device. B means of computation a certain len h of the rail is predetermined which is ismounted from the sleepers in one direction from the place of repairing. About-the middle of-the dismounted stretch a force P provided, which is adapted to bend the rail 1 in the plane of the least moment of resistance at the rightangle to its length to produce the required gap 3 at the ]o1nt to be welded. It is necessary that the end of rail 1 be moved lengthwise easily and ppsitively without tilting, preferably by guiding it by means of the indicated rollers 4, and.

that the opposite end 5 of the dismounted stretch be securely held.

For the generation of the jumping pressure required in a welding connection and for the purpose of giving assistance to the force P, a force R is brought into action lengthwise of the rail at a short distance from the joint to be welded.

Another supposition for this method is, that there is no gap at the point of welding 6 in Fig. 3. but that there is a suitable overlapping 7, Fig. 4 to compensate the shortening of the rail at the welding point.

In the case that a break occurs during summer at a temperature above normal, this condition is fulfilled by the expansion caused in the rail itself. According to the temperature prevailing in winter a greater or lesser gap may arise at the point of breakage, which must be closed up, before welding can be begun. The simplest manner in which this may be done, is to warm up a stretch of the rail on one or on both sides adjacent to the part, which is to be repaired with a set of heating flames or with electricity to such an extent, that the abutting of 1: 1 and a cylinder diameter of about only parts of the joint will overlap instead of having a gap 6 between them. A computation shows, that the required force of movement and the stress arising when the rail is bent, are within .absolutely acceptable limits, so that repair welding on the line can be done quickly and with comparatively simple means. With the rail profiles commonly used a length 8 of about 21-27 meters must be dismounted and bent out to the distance of 40-64 cms. 9 in order to obtain a burning-off and jumping length 10 of 2-4 cms., whereby the elastic limit of the rail material of about 3000 kgs./cm. is not exceeded in bending operation. The force at the point of bending will thereby be about 500 kgs. and is therefore increased by the forces of friction easily obtainable by means of either mechanical or hydraulic devices.

The jumping pressure required, according to the method which is adopted, lies between and 300 kgs. cm.'- of the welding section- :11 area, and amounts therefore in a sectional ip'ca of 60 cm. to the maximum of 18000 With an hydraulic device of 50 atmospheres liquid pressure, this result can be secured with the transmission in proportion The moving devices may be actuated mechanically, electromechamcally or hydraulically. A condition 'for satisfactory operation 1s, that the movement of the end of the rail, i. c. the motive forces P and R can be controlled from a lace in the immediate neighbourhood of 't 1e joint which is to be welded, so that these forces, according to the arrangement desired, will act singly or jointly and that they are timed automatically in relation to one another in such a manner, that the bending line of the dismounted part of therail is always in all its conditions of movement a simple one without intermediate bends (Fig. 6), which would increase the strain on the rail mate rial beyond its capacity.

When welding smaller cross sectional areas the movements may be carriedout manually, preferably by providing an intermediate second transmission, so as to attain the required jumping pressure, whereas for larger sectional areas, electromechanical or hydraulic devices, because of their simple means forattaining high forces, are preferable.

The steering apparatus and the course of the liquid for this arrangement is shown diagrammatically in Fig. 7 wherein the liquid flow of both cylinders is regulated by one steering valve, which is actuated manually and arranged in such a manner, that every position of the moved rail is determined by a certain position of the hand lever. The moving operations of the first modification according to Fig. 7 are as follows: The pressure liquid coming from the conduit 'pipe 11 passes through the chamber 12 which is formed by the slide valve chest 13 and the steering shell 14 and from there into the chamber 15. When the hand lever 16 and therewith the steering piston 17 is moved to the left as shown in Fig. 7 the pressure liquid enters the chamber 18 through the opening 19 which has opened.

From here it flows through the conduit pipe 20 to the cylinder 21 and further to the conduit pipe 22 and the cylinder The conj duit pipe 24 is closed in this direction by means of the cheek non-return valve 25. The pistons 26 and 27 now move in the directions indicated by the arrows until pivoted return lever 28, which is moved by the piston rod 3 29 has moved the steering shell 14 so far with respect to the steering piston 17, that the openings 19 are closed.

During movements which follow rapidly one after another the tandem arrangement 1 of the cylinders will counteract in itself any intermediate bendings of the rail, as the crosswise cylinder will be favored with ressure liquid vwhen the rail is bent anc the lengthwise cylinder when the rail is straightened.

In order to prevent any'po'ssible inter mediate bending, particularly at the start of the rail movement, throttled slide valves 30 are provided in conduits 22 and 31. One of such -'valves is shown in section in Fig. 8. Liquid from pi pc 22 passes into cylinder 32 to thereby act uponthe connected pistons 33am? 39. A pipe of smaller diameter than pipe 22 also allows the fluid under pressure to flow into cylinder 35 to thereby act upon the opposite face of piston 33. Pressure is thus gradually built up in cylinder 35 to raise pistons 33 and 34 against the tension of the adjustable spring 36, thus exposing openings in cylinder 32 whereby the liquid may pass throughto the other connection of pipe 22.

To bend the rail, the hand lever 16 is moved to the right. Liquid under pressure then may pass into conduit 37, sinceplunge-r 17 exposes the proper openings in chamber 13. This liquid enters cylinder 23 above piston 27 toforce the same downwardly to thus bend the rail. Liquid also passes through conduit 31 to cylinder 21 to the right of piston 26. from the opposite sides of by the one-way valves 25.

For clearness the rail is indicated by dotted lines 38.

pistons 27 and 26 By means of a cylinder '39 which is arof a pressure liquid. Consequently the de-.

vice for clamping and guiding the ends of the rails in connection with hydraulic cylindcr and moving mechanism maybe the same as that previously described.

The steering slider may also be the same as in Figs. 7 and 8 with the limitation of the conduit to only one double acting cylinder 21. Y

The bending of the rail in this example is done mechanically by spring motive power 7 which isnot immediately controlled. The

arrangement provides two springs 42, 43 which act on the rail by means of the linkarms 44, 45. The system of joints is designed in such a maner, that the bending force increases steadily with the increase'of the deflection. In orderto avoid absolutely intermediate bendings, which for instance may arise when one spring is seized or a jamming in the guides occurs or something similar happens, the rail is moved at numerous points in such a manner, that the most favorable bending line is obtained in all positions.

In the present case, there are, besides the system 0 links in the middle of the dismounted rail' stretch, also two more systems of links each distanced 1/41 from the place where the rail is clamped. The link arms 56 and 47 are half as long as the link arms 44 and 45. The link points 48 are firmly located whereas the link points 49 are Pressure is relieved.

whichcomprises detaching a long section of I the rail from its supports, stretching said detached section longitudinally-in the original direction of said rail into abutting engagement with the adjacent section, and welding said abutting ends.

2. The method of jointlessly welding the rails of railway tracks and repairing the same on the lines without removal thereof, which comprises detaching a long section of'rail from its supports, bending said detached section out of longitudinal alignment, stretching said detached section longitudinally and into abutting engagement with an adjacent section, and welding said abutting ends.

3. The method of jointlessly welding the rails of railway tracks and repairing the same on the lines without removal thereof, which comprises detaching a 'lon section of the rail from its supports, ben ing said detached portion out .of longitudinal alignment to such extent that the greatest stress on the rail is below the limit of elasticity thereof to thus secure longitudinal movement of the end of said detached portion for welding purposes, and welding the end of said portion to the adjacent rail section.

4. The method of jointlessly welding the rails of railway tracks and repairing the same on the line without removal thereof,

which comprises detaching a long section of the rail from its supports, heating said rail section to cause longitudinal expansionthereof such that the end will overlap the adjacent section sufficient for jumping pressure, bending the mid section of the detached portion out of longitudinal align-' ment, placing the end thereof in longitu-' dinal alignment with the adjacent rail section, allowing the bent. out section to straighten to thereby secure 'the necessar jumping pressure, and simultaneously wel ing the end of said detached rail section to the adjacent rail section.

5. In the method of jointlessly welding I the rails of railway tracks and repairing the same on the line without removal thereof by electrical melting-off welding, the step which comprisesdetaching a long section of the rail from its supports, applying a stretching force to said detached section, applying a bending force to said section, automatically timing the application of said forces ,with respect to one another in such manner that the rail section assumes a simple bend without intermediate bends.

6. The method of jointlessl welding the rails of railway tracks wit out removal thereof, which comprises detaching a long section of rail from its supports, movin the end of said detached section back and forth longitudinally for electrical meltingofl welding by two separately. acting forces on said section, one of said forces being applied longitudinally of the detached section adjacent the end thereof, and the other of said forces being applied cross-wise of said section to bend the same.

CURT STEDEFELD. 

